petal(redirected from Zygomorph)
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petal,one of the four basic parts of a flowerflower,
name for the specialized part of a plant containing the reproductive organs, applied to angiosperms only. A flower may be thought of as a modified, short, compact branch bearing lateral appendages.
..... Click the link for more information. , next innermost organ from the sepal. The whorl of petals is known collectively as the corolla [Lat.,=little crown]. The number of petals is usually constant within groups (e.g., five in the rose family), as are the numbers of the other organs. Identification by number is, however, complicated by various factors; the petals may be fused, inconspicuous, or entirely absent, in which case their role as the showy part of the flower is sometimes supplanted by modified leaves, the bracts, as in the dogwood and poinsettia, or by modified stamens, as in the canna and the lady's-slipper. Selective breeding can produce petallike stamens (e.g., in cultivated roses and geraniums) and so-called double flowers, i.e., varieties with more than the normal number of petals. Petals are usually brightly colored and often secrete perfume and nectar (in nectaries at the base of the petal) that attract insects and birds needed for cross-pollination. When fertilization has taken place the petals usually drop off; however, in some flowers they persist (see everlastingeverlasting
, names for numerous plants characterized by papery or chaffy flowers that retain their form and often their color when dried and are used for winter bouquets and decorations.
..... Click the link for more information. ). In general there are fewer petals and their fusion is greater as the evolutionary development increases. Radially symmetrical arrangement also gives way to bilateral symmetry or even asymmetry.
a leaflike member of the corolla in a flower, which is generally brightly colored. In sympetalous plants, the petals are grown together to some degree. The leaflets of simple corolliform perianths are sometimes erroneously called petals.
One of the sterile, leaf-shaped flower parts that make up the corolla.
One of the overlapping shingles or tiles in imbrication.
any of the separate parts of the corolla of a flower: often brightly coloured